Java tutorial
/** * This file is part of Graylog Pipeline Processor. * * Graylog Pipeline Processor is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Graylog Pipeline Processor is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Graylog Pipeline Processor. If not, see <http://www.gnu.org/licenses/>. */ package org.graylog.plugins.pipelineprocessor.functions.dates; import com.google.common.collect.ImmutableList; import org.graylog.plugins.pipelineprocessor.EvaluationContext; import org.graylog.plugins.pipelineprocessor.ast.functions.FunctionArgs; import org.graylog.plugins.pipelineprocessor.ast.functions.ParameterDescriptor; import org.joda.time.DateTime; import org.joda.time.DateTimeZone; import org.joda.time.format.DateTimeFormat; import org.joda.time.format.DateTimeFormatter; public class ParseDate extends TimezoneAwareFunction { public static final String NAME = "parse_date"; public static final String VALUE = "value"; public static final String PATTERN = "pattern"; private final ParameterDescriptor<String, String> valueParam; private final ParameterDescriptor<String, String> patternParam; public ParseDate() { valueParam = ParameterDescriptor.string(VALUE).description("Date string to parse").build(); patternParam = ParameterDescriptor.string(PATTERN).description( "The pattern to parse the date with, see http://www.joda.org/joda-time/apidocs/org/joda/time/format/DateTimeFormat.html") .build(); } @Override protected String getName() { return NAME; } @Override protected ImmutableList<ParameterDescriptor> params() { return ImmutableList.of(valueParam, patternParam); } @Override public DateTime evaluate(FunctionArgs args, EvaluationContext context, DateTimeZone timezone) { final String dateString = valueParam.required(args, context); final String pattern = patternParam.required(args, context); if (dateString == null || pattern == null) { return null; } final DateTimeFormatter formatter = DateTimeFormat.forPattern(pattern).withZone(timezone); return formatter.parseDateTime(dateString); } @Override protected String description() { return "Parses a date string using the given date format"; } }